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For test.pl
  Run on Mon Apr 5 14:31:27 2021
Reported on Mon Apr 5 14:31:40 2021

Filename/home/leont/perl5/perlbrew/perls/perl-5.32.0/lib/5.32.0/XSLoader.pm
StatementsExecuted 0 statements in 0s
Subroutines
Calls P F Exclusive
Time
Inclusive
Time
Subroutine
111100µs100µsXSLoader::::loadXSLoader::load
0000s0sXSLoader::::bootstrap_inheritXSLoader::bootstrap_inherit
Call graph for these subroutines as a Graphviz dot language file.
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Code
1# Generated from XSLoader_pm.PL (resolved %Config::Config value)
2# This file is unique for every OS
3
4package XSLoader;
5
6$VERSION = "0.30"; # remember to update version in POD!
7
8#use strict;
9
10package DynaLoader;
11
12# No prizes for guessing why we don't say 'bootstrap DynaLoader;' here.
13# NOTE: All dl_*.xs (including dl_none.xs) define a dl_error() XSUB
14boot_DynaLoader('DynaLoader') if defined(&boot_DynaLoader) &&
15 !defined(&dl_error);
16package XSLoader;
17
18
# spent 100µs within XSLoader::load which was called: # once (100µs+0s) by CPAN::Meta::Prereqs::BEGIN@17 at line 24 of List/Util.pm
sub load {
19 package DynaLoader;
20
21 my ($caller, $modlibname) = caller();
22 my $module = $caller;
23
24 if (@_) {
25 $module = $_[0];
26 } else {
27 $_[0] = $module;
28 }
29
30 # work with static linking too
31 my $boots = "$module\::bootstrap";
32 goto &$boots if defined &$boots;
33
34 goto \&XSLoader::bootstrap_inherit unless $module and defined &dl_load_file;
35
36 my @modparts = split(/::/,$module);
37 my $modfname = $modparts[-1];
38 my $modfname_orig = $modfname; # For .bs file search
39
40 my $modpname = join('/',@modparts);
41 my $c = () = split(/::/,$caller,-1);
42 $modlibname =~ s,[\\/][^\\/]+$,, while $c--; # Q&D basename
43 # Does this look like a relative path?
44 if ($modlibname !~ m{^/}) {
45 # Someone may have a #line directive that changes the file name, or
46 # may be calling XSLoader::load from inside a string eval. We cer-
47 # tainly do not want to go loading some code that is not in @INC,
48 # as it could be untrusted.
49 #
50 # We could just fall back to DynaLoader here, but then the rest of
51 # this function would go untested in the perl core, since all @INC
52 # paths are relative during testing. That would be a time bomb
53 # waiting to happen, since bugs could be introduced into the code.
54 #
55 # So look through @INC to see if $modlibname is in it. A rela-
56 # tive $modlibname is not a common occurrence, so this block is
57 # not hot code.
58 FOUND: {
59 for (@INC) {
60 if ($_ eq $modlibname) {
61 last FOUND;
62 }
63 }
64 # Not found. Fall back to DynaLoader.
65 goto \&XSLoader::bootstrap_inherit;
66 }
67 }
68 my $file = "$modlibname/auto/$modpname/$modfname.so";
69
70# print STDERR "XSLoader::load for $module ($file)\n" if $dl_debug;
71
72 # N.B. The .bs file does not following the naming convention used
73 # by mod2fname, so use the unedited version of the name.
74
75 my $bs = "$modlibname/auto/$modpname/$modfname_orig.bs";
76
77 # This calls DynaLoader::bootstrap, which will load the .bs file if present
78 goto \&XSLoader::bootstrap_inherit if not -f $file or -s $bs;
79
80 my $bootname = "boot_$module";
81 $bootname =~ s/\W/_/g;
82 @DynaLoader::dl_require_symbols = ($bootname);
83
84 my $boot_symbol_ref;
85
86 # Many dynamic extension loading problems will appear to come from
87 # this section of code: XYZ failed at line 123 of DynaLoader.pm.
88 # Often these errors are actually occurring in the initialisation
89 # C code of the extension XS file. Perl reports the error as being
90 # in this perl code simply because this was the last perl code
91 # it executed.
92
93 my $libref = dl_load_file($file, 0) or do {
94 require Carp;
95 Carp::croak("Can't load '$file' for module $module: " . dl_error());
96 };
97 push(@DynaLoader::dl_librefs,$libref); # record loaded object
98
99 $boot_symbol_ref = dl_find_symbol($libref, $bootname) or do {
100 require Carp;
101 Carp::croak("Can't find '$bootname' symbol in $file\n");
102 };
103
104 push(@DynaLoader::dl_modules, $module); # record loaded module
105
106 boot:
107 my $xs = dl_install_xsub($boots, $boot_symbol_ref, $file);
108
109 # See comment block above
110 push(@DynaLoader::dl_shared_objects, $file); # record files loaded
111 return &$xs(@_);
112}
113
114sub bootstrap_inherit {
115 require DynaLoader;
116 goto \&DynaLoader::bootstrap_inherit;
117}
118
1191;
120
121
122__END__
123
124=head1 NAME
125
126XSLoader - Dynamically load C libraries into Perl code
127
128=head1 VERSION
129
130Version 0.30
131
132=head1 SYNOPSIS
133
134 package YourPackage;
135 require XSLoader;
136
137 XSLoader::load(__PACKAGE__, $VERSION);
138
139=head1 DESCRIPTION
140
141This module defines a standard I<simplified> interface to the dynamic
142linking mechanisms available on many platforms. Its primary purpose is
143to implement cheap automatic dynamic loading of Perl modules.
144
145For a more complicated interface, see L<DynaLoader>. Many (most)
146features of C<DynaLoader> are not implemented in C<XSLoader>, like for
147example the C<dl_load_flags>, not honored by C<XSLoader>.
148
149=head2 Migration from C<DynaLoader>
150
151A typical module using L<DynaLoader|DynaLoader> starts like this:
152
153 package YourPackage;
154 require DynaLoader;
155
156 our @ISA = qw( OnePackage OtherPackage DynaLoader );
157 our $VERSION = '0.01';
158 __PACKAGE__->bootstrap($VERSION);
159
160Change this to
161
162 package YourPackage;
163 use XSLoader;
164
165 our @ISA = qw( OnePackage OtherPackage );
166 our $VERSION = '0.01';
167 XSLoader::load(__PACKAGE__, $VERSION);
168
169In other words: replace C<require DynaLoader> by C<use XSLoader>, remove
170C<DynaLoader> from C<@ISA>, change C<bootstrap> by C<XSLoader::load>. Do not
171forget to quote the name of your package on the C<XSLoader::load> line,
172and add comma (C<,>) before the arguments (C<$VERSION> above).
173
174Of course, if C<@ISA> contained only C<DynaLoader>, there is no need to have
175the C<@ISA> assignment at all; moreover, if instead of C<our> one uses the
176more backward-compatible
177
178 use vars qw($VERSION @ISA);
179
180one can remove this reference to C<@ISA> together with the C<@ISA> assignment.
181
182If no C<$VERSION> was specified on the C<bootstrap> line, the last line becomes
183
184 XSLoader::load(__PACKAGE__);
185
186in which case it can be further simplified to
187
188 XSLoader::load();
189
190as C<load> will use C<caller> to determine the package.
191
192=head2 Backward compatible boilerplate
193
194If you want to have your cake and eat it too, you need a more complicated
195boilerplate.
196
197 package YourPackage;
198
199 our @ISA = qw( OnePackage OtherPackage );
200 our $VERSION = '0.01';
201 eval {
202 require XSLoader;
203 XSLoader::load(__PACKAGE__, $VERSION);
204 1;
205 } or do {
206 require DynaLoader;
207 push @ISA, 'DynaLoader';
208 __PACKAGE__->bootstrap($VERSION);
209 };
210
211The parentheses about C<XSLoader::load()> arguments are needed since we replaced
212C<use XSLoader> by C<require>, so the compiler does not know that a function
213C<XSLoader::load()> is present.
214
215This boilerplate uses the low-overhead C<XSLoader> if present; if used with
216an antique Perl which has no C<XSLoader>, it falls back to using C<DynaLoader>.
217
218=head1 Order of initialization: early load()
219
220I<Skip this section if the XSUB functions are supposed to be called from other
221modules only; read it only if you call your XSUBs from the code in your module,
222or have a C<BOOT:> section in your XS file (see L<perlxs/"The BOOT: Keyword">).
223What is described here is equally applicable to the L<DynaLoader|DynaLoader>
224interface.>
225
226A sufficiently complicated module using XS would have both Perl code (defined
227in F<YourPackage.pm>) and XS code (defined in F<YourPackage.xs>). If this
228Perl code makes calls into this XS code, and/or this XS code makes calls to
229the Perl code, one should be careful with the order of initialization.
230
231The call to C<XSLoader::load()> (or C<bootstrap()>) calls the module's
232bootstrap code. For modules build by F<xsubpp> (nearly all modules) this
233has three side effects:
234
235=over
236
237=item *
238
239A sanity check is done to ensure that the versions of the F<.pm> and the
240(compiled) F<.xs> parts are compatible. If C<$VERSION> was specified, this
241is used for the check. If not specified, it defaults to
242C<$XS_VERSION // $VERSION> (in the module's namespace)
243
244=item *
245
246the XSUBs are made accessible from Perl
247
248=item *
249
250if a C<BOOT:> section was present in the F<.xs> file, the code there is called.
251
252=back
253
254Consequently, if the code in the F<.pm> file makes calls to these XSUBs, it is
255convenient to have XSUBs installed before the Perl code is defined; for
256example, this makes prototypes for XSUBs visible to this Perl code.
257Alternatively, if the C<BOOT:> section makes calls to Perl functions (or
258uses Perl variables) defined in the F<.pm> file, they must be defined prior to
259the call to C<XSLoader::load()> (or C<bootstrap()>).
260
261The first situation being much more frequent, it makes sense to rewrite the
262boilerplate as
263
264 package YourPackage;
265 use XSLoader;
266 our ($VERSION, @ISA);
267
268 BEGIN {
269 @ISA = qw( OnePackage OtherPackage );
270 $VERSION = '0.01';
271
272 # Put Perl code used in the BOOT: section here
273
274 XSLoader::load(__PACKAGE__, $VERSION);
275 }
276
277 # Put Perl code making calls into XSUBs here
278
279=head2 The most hairy case
280
281If the interdependence of your C<BOOT:> section and Perl code is
282more complicated than this (e.g., the C<BOOT:> section makes calls to Perl
283functions which make calls to XSUBs with prototypes), get rid of the C<BOOT:>
284section altogether. Replace it with a function C<onBOOT()>, and call it like
285this:
286
287 package YourPackage;
288 use XSLoader;
289 our ($VERSION, @ISA);
290
291 BEGIN {
292 @ISA = qw( OnePackage OtherPackage );
293 $VERSION = '0.01';
294 XSLoader::load(__PACKAGE__, $VERSION);
295 }
296
297 # Put Perl code used in onBOOT() function here; calls to XSUBs are
298 # prototype-checked.
299
300 onBOOT;
301
302 # Put Perl initialization code assuming that XS is initialized here
303
304
305=head1 DIAGNOSTICS
306
307=over
308
309=item C<Can't find '%s' symbol in %s>
310
311B<(F)> The bootstrap symbol could not be found in the extension module.
312
313=item C<Can't load '%s' for module %s: %s>
314
315B<(F)> The loading or initialisation of the extension module failed.
316The detailed error follows.
317
318=item C<Undefined symbols present after loading %s: %s>
319
320B<(W)> As the message says, some symbols stay undefined although the
321extension module was correctly loaded and initialised. The list of undefined
322symbols follows.
323
324=back
325
326=head1 LIMITATIONS
327
328To reduce the overhead as much as possible, only one possible location
329is checked to find the extension DLL (this location is where C<make install>
330would put the DLL). If not found, the search for the DLL is transparently
331delegated to C<DynaLoader>, which looks for the DLL along the C<@INC> list.
332
333In particular, this is applicable to the structure of C<@INC> used for testing
334not-yet-installed extensions. This means that running uninstalled extensions
335may have much more overhead than running the same extensions after
336C<make install>.
337
338
339=head1 KNOWN BUGS
340
341The new simpler way to call C<XSLoader::load()> with no arguments at all
342does not work on Perl 5.8.4 and 5.8.5.
343
344
345=head1 BUGS
346
347Please report any bugs or feature requests via the perlbug(1) utility.
348
349
350=head1 SEE ALSO
351
352L<DynaLoader>
353
354
355=head1 AUTHORS
356
357Ilya Zakharevich originally extracted C<XSLoader> from C<DynaLoader>.
358
359CPAN version is currently maintained by SE<eacute>bastien Aperghis-Tramoni
360E<lt>sebastien@aperghis.netE<gt>.
361
362Previous maintainer was Michael G Schwern <schwern@pobox.com>.
363
364
365=head1 COPYRIGHT & LICENSE
366
367Copyright (C) 1990-2011 by Larry Wall and others.
368
369This program is free software; you can redistribute it and/or modify
370it under the same terms as Perl itself.
371
372=cut